On this date in 2019, a space craft containing tardigrades crashed on the Moon. Here are 10 things you might not know about tardigrades:
The word tardigrade means “slow-moving.” They are also known as “water bears” and “moss piglets”.
There are about 1,300 species of tardigrade, and they are found just about everywhere, because they can survive just about anything. Scientists have found they can live through temperatures of 0.05 kelvins (-272.95 degrees Celsius or functional absolute zero), and at the other extreme, temperatures of 150 degrees Celsius. They can withstand extremely high pressure – they have survived being shot from a gun. Radiation is no problem to them, either. They can survive in space and would probably even survive a nuclear explosion. They have survived all five mass extinction events and have been around since way before the Dinosaurs. Scientists estimate that tardigrades have been around for 600 million years. Dinosaurs first appeared about 230 million years ago.
How do they do it? You may ask. It’s because they are capable of entering a cryptobiotic state when the going gets tough. It’s called a tun state; the creature curls into a ball, slows its metabolism down to virtually nothing and waits until conditions get better. A tardigrade can exist in this state for as much as a century and re-animate successfully.
That said, when they are not in the tun state, they don’t live anything like as long. Outside their tun state, they live between 3 months and 2.5 years.
So does that mean the tardigrades on the moon are busy colonising up there? Unlikely. While scientists think they may well have survived the crash, they can’t re-animate without Water, and what would they eat, anyway?
So what do they eat here on Earth? The answer is mostly plants and algae, although some species eat smaller creatures, like microscopic worms or tiny, wheel-shaped animals called rotifers.
They are microscopic. The largest species may reach 1.3 mm (0.051 in). They are short and plump, with four pairs of legs, ending in claws or sticky pads. They are covered in a tough material similar to that of grasshoppers and other insects, and they must shed this outer skin in order to grow.
It is possible to observe them at home if you happen to have a microscope. A low magnification — 15x to 30x should be enough. Simply collect some moss and keep it in water overnight. Shake or squeeze the excess water from the moss and put it in a shallow dish such as a petri dish and you will probably see tardigrades using the microscope.
They were first described by the German zoologist Johann August Ephraim Goeze in 1773, who called them Kleiner Wasserbär 'little water bear'. In 1776, the Italian biologist Lazzaro Spallanzani named them Tardigrada, which means 'slow walker'. They have inspired science fiction writers, starting with geologist and explorer Douglas Mawson in 1908. He wrote a short story about an expedition to the South Pole where explorers encounter all manner of things, including giant mushrooms and tardigrades.
There’s even a song about them. It’s by Cosmo Sheldrake and the lyrics go: "If I were a tardigrade ... Pressure wouldn't squash me and fire couldn't burn ... I can live life in vacuums for years with no drink (A ha)"
Beta
(Combat Team Series #2)
Steff was abducted by an evil alien race, the Orbs, at fourteen. Used as a weapon for years, he eventually escapes, but his problems are just beginning. How does a man support himself when his only work experience is a paper round and using an Orb bio-integrated gun?
Warlord is an alien soldier who knows little but war. When the centuries-old conflict which ravaged his planet ends, he seeks out another world where his skills are still relevant. There are always wars on Earth, it seems. However, none of Earth's powerful armies want him.
Natalie has always wanted to visit England and sees a chance to do so while using her martial arts skills, but there are sacrifices she must make in order to fulfil her dream.
Maggie resorted to crime to fund her sister's medical care. She uses her genetic variant abilities to gain access to the rooms of wealthy hotel guests. The Ballards look like rich pickings, but they are not what they seem. When Maggie targets them, little does she know that she is walking into a trap.
Hotel owner Hamilton Lonsdale puts together a combat team to pit against those of other multi-millionaires. He recruits Warlord, Natalie, Maggie and Steff along with a trained gorilla, a probability-altering alien, a stockbroker whose work of art proved to be much more than he'd bargained for, a marketing officer who can create psionic forcefields, a teleporting member of the landed gentry, and a socially awkward fixer. This is Combat Team Beta.
Steff never talks about his time with the Orbs, until he finds a woman who lived through it, too. Steff believes he has finally found happiness, but it is destined to be short-lived. He is left with an unusual legacy which he and Team Beta struggle to comprehend; including why something out there seems determined to destroy it.
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